If you have upgraded Julia to version 1.8 and are still seeing an old non-existent Julia kernel in Jupyter, there are a few different ways to solve this issue. In this article, we will explore three possible solutions.
Solution 1: Restart Jupyter Kernel
The first solution is to simply restart the Jupyter kernel. This can be done by going to the Jupyter notebook interface, selecting “Kernel” from the top menu, and then choosing “Restart Kernel”. This will terminate the current kernel and start a new one, which should no longer include the old non-existent Julia kernel.
# Restart Jupyter kernel
Kernel > Restart Kernel
Solution 2: Remove Old Julia Kernel
If restarting the kernel does not solve the issue, you can try removing the old Julia kernel from Jupyter. To do this, you will need to access the Jupyter kernel directory and delete the relevant files. The exact location of the kernel directory may vary depending on your operating system and Jupyter installation.
# Find the Jupyter kernel directory
jupyter --paths
# Navigate to the kernel directory
cd
# Remove the old Julia kernel files
rm -rf julia-
Solution 3: Reinstall Julia Kernel
If neither of the previous solutions work, you can try reinstalling the Julia kernel in Jupyter. This will ensure that you have the latest version of the Julia kernel and that any old or non-existent kernels are removed.
# Install Julia kernel
using Pkg
Pkg.add("IJulia")
After trying these three solutions, it is recommended to restart Jupyter and check if the old non-existent Julia kernel still appears. If it does not, then the best option would be Solution 1: Restart Jupyter Kernel, as it is the simplest and quickest solution. However, if the issue persists, you can try Solution 2: Remove Old Julia Kernel or Solution 3: Reinstall Julia Kernel to ensure a clean and up-to-date Jupyter environment.
